In terms of overall quality (consisting of award seat availability, product, comfort, reliability etc)
Qantas, JAL, ANA, Emirates, Singapore. Just your general opinion is good enough
Do you have any others that you would like to mention as particularly good?
For me, Singapore Airlines is the most consistent in terms of award space availability (if booking well in advance) and level of service (some would say too consistent). Unfortunately, Krisflyer miles is harder to earn than Qantas or Velocity points in Australia (which could be partly why competition is higher with other Qantas and Velocity members).